Method of shearing thin plate

ABSTRACT

Provided is a method of shearing a thin plate with high quality without a need for narrowing a clearance by precision machining. The method comprises: placing a thin plate ( 1 ) having at least one non-metal layer ( 1   b ), between a punch ( 3 ) and a die ( 2 ) having a shearing hole ( 2   a ); and relatively moving the punch ( 3 ) toward and with respect to the shearing hole ( 2   a ) to thereby shear the thin plate ( 1 ), wherein the relative movement of the punch ( 3 ) is stopped to complete the shearing, before the punch ( 3 ) penetrates through the thin plate ( 1 ) and becomes fitted into the shearing hole ( 2   a ).

TECHNICAL FIELD

The present invention relates to a method of shearing a thin plate, andmore specifically to a method for forming a product by shearing a thinplate with a thickness of about 0.5 mm or less, which is made of a metalor prepared by laminating one or more non-metal layers on one orrespective ones of opposite surfaces of a metal layer.

BACKGROUND ART

As a technique for forming a product from a thin plate, a method ofpunching (blanking) a thin plate using a forming tool (punch and die) ismost common.

In the punching (blanking) method, the workpiece plate is subjected toshearing by placing a workpiece plate on a die having a punch hole, andmoving a punch disposed just above the punch hole downwardly to allow adistal end of the punch to be fitted into the punch hole. In some cases,the punch and the die are disposed upside down, i.e., the punch isdisposed just below the die, and the die is moved instead of the punch.

In regard to conditions for the punching, considerable researches haveheretofore been made. For example, the following Non-Patent Document 1discloses an adequate relationship between a thickness of a workpieceplate, and a gap between a punch and a die (punch hole) for punching theworkpiece plate (the gap will hereinafter be referred to simply as“clearance”). In the Non-Patent Document 1, an adequate clearance isdescribed as about 5 to 10% of the thickness of the workpiece plate.

According to this relationship between the thickness of the workpieceplate and the clearance, when the workpiece plate has a thickness of 1mm, the clearance is in the range of about 50 to 100 μm. As long as theclearance is such a value, it is easy to fabricate a forming tool, etc.However, when the workpiece plate has a smaller thickness, e.g., athickness of 20 μm, the adequate clearance is reduced to 1 to 2 μm, sothat a high level of fabrication technique, such as precision machining,is required for a forming tool, which leads to a problem of an increasein cost.

Moreover, a punching operation using a forming tool fabricated to have anarrowed clearance involves other problems. One problem is a reductionin usable life of the forming tool due to wear of the punch and the die.Specifically, a narrower clearance leads to a higher frequency ofcontact between the punch and the die in elastic deformation rangesthereof, which accelerates wear thereof. Further, if the punch and thedie are deformed beyond the elastic deformation ranges during thecontact therebetween, a problem of chipping will also occur.

Another major problem is a problem with debris to be generated from aworkpiece plate during punching. This problem becomes prominent when theworkpiece plate is a laminated plate comprised of a metal layer and anon-metal layer. Debris generated from a workpiece plate is trappedbetween the punch and the die, which causes various problems, such as aproblem of an increase in force required for punching, and a problem ofan increase in frequency of cleaning required for the punch and the die.Moreover, the debris is likely to cause breakage of the forming tool.

The conventional punching method has another problem. Specifically,along with punching of a workpiece plate, particularly a metal plate,depending on its compatibility with a forming tool, adhesion of theworkpiece plate is likely to occur in a punch. It is possible to preventthe adhesion problem to some extent by coating a punch and a die withceramics, DLC (Diamond-Like Carbon) or the like. However, in a formingtool having a narrow clearance, only a temporary effect can be obtainedbecause large wear occurs in a punch and a die due to a sliding movementtherebetween.

Still another problem is deterioration in quality of an outer edge of apunched-out portion of the workpiece plate (product portion). This isbecause, after punching the workpiece plate, the punched-out portion ismoved to a dead center position of the punch while rubbing against aninner surface of the die, i.e., placed in a rubbing state through untilit is separated from the die.

As above, in shearing based on the conventional punching method, variousproblems occurs, particularly, when a workpiece plate has a smallthickness.

PRIOR ART DOCUMENTS Non-Patent Documents

-   Non-Patent Document 1: A. Hashimoto, “Press Operations & Die    Machining Methods New Edition”, 7th Edition, Nikkan Kogyo Shimbun,    Ltd., Apr. 30, 1975, p 35

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

In view of the above various problems involved in shearing based on theconventional punching method, it is an object of the present inventionto provide a method capable of shearing a thin plate with high qualityover a long period of time, and significantly excellently shearing athin plate based on a low-cost forming tool and a low-cost process,without the necessity to subject a forming tool for use in the shearingto precision machining.

Means for Solving the Problem

Through various researches on shearing of thin plates, the inventorfound that, in a thin plate prepared by laminating one or more non-metallayers on one or respective ones of opposite surfaces of a metal layer,the thin plate is fully sheared before a punch penetrates through thethin plate and becomes fitted into a shearing hole of a die.

The present invention has been made based on the above finding.Specifically, the present invention provides a method of shearing a thinplate prepared by laminating one or more non-metal layers on one orrespective ones of opposite surfaces of a metal layer. The methodcomprises: placing the thin plate between a punch and a die having ashearing hole; and relatively moving the punch toward and with respectto the shearing hole to thereby shear the thin plate, wherein therelative movement of the punch is stopped to complete the shearing,before the punch penetrates through the thin plate and becomes fittedinto the shearing hole.

As above, in the present invention, the punch is not fitted into thedie, so that it is not necessary to severely adjust a clearance as inthe conventional punching method designed to allow the punch to befitted into the die. Thus, the clearance may be set to a zero clearance,or a minus clearance in which an outer diameter of the punch is set tobe greater than an inner diameter of the die, as well as an usual plusclearance. In other words, in the present invention, it is not necessaryto severely adjust a clearance based on precision machining of a formingtool (punch and die), so that it becomes possible to easily fabricatethe forming tool and reduce a fabrication cost of the forming tool.

In addition, based on the feature that the punch is not fitted into thedie, each of the punch and the die becomes less likely to be worn, whichprovides extended usable life of the forming tool. Further, adisplacement of a sheared portion of a workpiece plate is reduced, andthereby an amount of debris to be generated is reduced. The conventionalmethod also has a problem that, along with a vertical movement of thepunch, a metal portion of a workpiece plate in contact with the punchadheres to the punch. It is difficult to remove the adhered metalcomponent. If it is tried to remove the adhered metal component byrubbing or scraping, or using chemicals, a surface of the punch willhave scars, or higher roughness, or alteration due to corrosion.Moreover, the adhesion phenomenon occurs after 100 shots at the latest,or after only 5 to 10 shots at the earliest. In contrast, in the methodof the present invention, the shearing can be performed without bringingthe punch into direct contact with a metal portion of a workpiece plate,so that it becomes possible to prevent the workpiece plate from adheringto the punch.

Thus, a shearing state can be excellently maintained, and the thin platecan be sheared with high quality. As for a forming tool, there is noneed to fabricate a forming tool with a maximally narrowed clearancewhich causes difficulty in fabrication and leads to a high cost, andtherefore there is no need to take a high cost for fabrication of aforming tool.

Meanwhile, in the technical field of punching (blanking), there has beenknown a method of punching a workpiece plate by subjecting the workpieceplate to half blanking in one direction, and then subjecting theworkpiece plate to reversed blanking, instead of punching the workpieceplate by a single punching operation (see, for example, JP 2004-167547Aand JP 2001-300647A). The shearing method of the present invention isessentially different from the conventional half blanking/reversedblanking technique, in that the shearing method is designed to fullyshear a workpiece plate by a single shearing operation.

Preferably, in the present invention, the punch is stopped at a positioncorresponding to a depth in the thin plate which is equal to or greaterthan a thickness of the metal layer and equal to or less than a totalthickness of the one or more non-metal layers. If the depthcorresponding to the stop position of the punch is less than thethickness of the metal layer, a possibility to fail to complete theshearing of the thin plate will be increased. Further, if the depth isgreater than the total thickness of the one or more non-metal layers,chipping in the punch and the die, an increase in amount of debrisand/or adhesion of a metal component of the thin plate to the punch willoccur, which is likely to cause difficulty in sufficiently obtain theeffects of the present invention.

Through experimental tests conducted by the inventor, it has been foundthat the shearing method of the present invention can also be applied toa thin plate stack formed by stacking a plurality of the thin plates oneach other. In this case, the thin plate stack is placed between thepunch and the die, and the relative movement of the punch is stopped tocomplete the shearing, before the punch penetrates through the thinplate stack and becomes fitted into the shearing hole. In this manner,the plurality of thin plates can be simultaneously sheared to provideenhanced productivity. In cases where a plurality of thin plates areoriginally used in the form of a laminated structure as in an electrodeplate for a lithium-ion battery, etc., a step of laminating respectivesheared portions of the thin plates can be omitted by simultaneouslyshearing the laminated thin plates. However, the number of the thinplates capable of being simultaneously sheared is about 10 at a maximum,in view of quality of a cut (sheared) surface of a workpiece plate. Ifthe number is excessively increased, the cut surface will be graduallyroughened, so that it becomes difficult to use resulting products in thefield requiring high quality. Preferably, in cases where a thin platestack formed by stacking a plurality of the thin plates on each other issimultaneously sheared, the punch is stopped at a position correspondinga depth in the thin plate stack which is equal to or greater than atotal thickness of the metal layers of the thin plate stack (a sum ofrespective thicknesses of the metal layers in the plurality of stakedthin plates) and equal to or less than a total thickness of thenon-metal layers of the thin plate stack (a sum of respectivethicknesses of the non-metal layers in the plurality of staked thinplates).

In addition to the shearing using the punch and the die, the shearingmethod of the present invention can also be applied to shearing using adie cutter and an anvil roll. Specifically, the present inventionprovides a method of shearing a thin plate prepared by laminating one ormore non-metal layers on one or respective ones of opposite surfaces ofa metal layer. The method comprises: inserting the thin plate between adie cutter provided with a convex push-cutting blade on a surfacethereof, and an anvil roll provided with a shearing recess at a positioncorresponding to the convex push-cutting blade; and rotating andpressing the convex push-cutting blade of the die cutter toward theshearing recess of the anvil roll to thereby shear the thin plate,wherein the thin plate is sheared without causing the convexpush-cutting blade of the die cutter to penetrate through the thin plateand become fitted into the shearing recess of the anvil roll. Thisshearing method also provides the same effects as those of the shearingusing the punch and the die. In other words, the thin plate is fullysheared before the convex push-cutting blade of the die cutterpenetrates through the thin plate and become fitted into the shearingrecess of the anvil roll.

Preferably, in the shearing method using the die cutter and the anvilroll, the convex push-cutting blade of the die cutter is thrust to aposition corresponding to a depth in the thin plate which is equal to orgreater than the thickness of the metal layer and equal to or less thanthe total thickness of the one or more non-metal layers.

Further, in order to more reliably shear the thin plate (i.e., workpieceplate) in the shearing method using the die cutter and the anvil roll,an intermediate plate having at least one non-metal layer may beinserted between the die cutter and the thin plate. Based on using theintermediate plate in the above manner, the thin plate can be morereliably sheared by a pressing effect arising from plastic flow of theintermediate plate. Preferably, in this case, the convex push-cuttingblade of the die cutter is thrust to a position corresponding to a depthin a combination of the intermediate plate and the thin plate which isequal to or greater than a total thickness of the metal layers of thethin plate and equal to or less than a total thickness of the one ormore non-metal layers of the thin plate and the intermediate plate.

In the present invention, in place of the die cutter provided with theconvex push-cutting blade on a surface thereof, a press roll devoid ofthe convex push-cutting blade may be used. Specifically, the presentinvention provides a method of shearing a thin plate prepared bylaminating one or more non-metal layers on one or respective ones ofopposite surfaces of a metal layer. The method comprises: inserting thethin plate between a press roll, and an anvil roll provided with ashearing recess; and rotating the press roll to press the thin platetoward the shearing recess of the anvil roll to thereby shear the thinplate, wherein an intermediate plate having at least one non-metal layeris inserted between the thin plate and the die cutter, and the thinplate is sheared without pressing the thin plate into the shearingrecess of the anvil roll beyond a thickness of the thin plate. In thisshearing method, the thin plate is fully sheared before the thin plateis fully pressed into the shearing recess of the anvil roll. Preferably,in this shearing method, the thin plate is pressed to a positioncorresponding to a depth in the shearing recess of the anvil roll whichis equal to or greater than a thickness of the metal layer and equal toor less than a total thickness of the one or more non-metal layers ofthe thin plate.

The shearing method using the die cutter or press roll and the anvilroll, a thin plate stack formed by stacking a plurality of the thinplates on each other may be inserted between the die cutter or pressroll and the anvil roll, to simultaneously shear the plurality ofstacked thin plates. Specifically, in the shearing method using the diecutter and the anvil roll, the thin plate stack is inserted between thedie cutter and the anvil roll, and all of the thin plates are shearedwithout causing the convex push-cutting blade of the die cutter topenetrate through the thin plate stack and become fitted into theshearing recess of the anvil roll. Preferably, in this case, the convexpush-cutting blade of the die cutter is thrust to a positioncorresponding to a depth in the thin plate stack which is equal to orgreater than a total thickness of the metal layers of the thin platestack and equal to or less than a total thickness of the non-metallayers of the thin plate stack. When the intermediate plate is used incombination, it is preferable that the convex push-cutting blade of thedie cutter is thrust to a position corresponding to a depth in acombination of the intermediate plate and the thin plate stack which isequal to or greater than a total thickness of the metal layers of thethin plate stack and equal to or less than a total thickness of thenon-metal layers of the thin plate stack and the intermediate plate.

On the other hand, in the shearing method using the press roll and theanvil roll, the thin plate stack is inserted between the press roll andthe anvil roll, and the intermediate plate having at least one non-metallayer is inserted between the thin plate stack and the press roll,whereafter the thin plate stack is sheared without pressing the thinplate stack into the shearing recess of the anvil roll beyond athickness of the thin plate stack. Preferably, in this case, the thinplate stack is pressed to a position corresponding to a depth in theshearing recess of the anvil roll which is equal to or greater than atotal thickness of the metal layers of the thin plate stack and equal toor less than a total thickness of the non-metal layers of the thin platestack.

In the present invention, in the shearing method using the press rolland the anvil roll, a surface of the press roll may be coated with alayer including at least one non-metal layer. Specifically, the presentinvention provides a method of shearing a thin plate which is made of ametal or prepared by laminating one or more non-metal layers on one orrespective ones of opposite surfaces of a metal layer. The methodcomprises: inserting the thin plate between a press roll having asurface coated with a layer including at least one non-metal layer, andan anvil roll provided with a shearing recess; and rotating the pressroll to press the thin plate toward the shearing recess of the anvilroll to thereby shear the thin plate, wherein the thin plate is shearedwithout pressing the thin plate into the shearing recess of the anvilroll beyond a thickness of the thin plate. Preferably, in this shearingmethod, the thin plate is pressed to a position corresponding to a depthin the shearing recess of the anvil roll which is equal to or greaterthan a thickness of the metal layer and equal to or less than a totalthickness of the one or more non-metal layers of the thin plate. In thisshearing method, when a plurality of the thin plates are stacked on eachother to form a thin plate stack, and the thin plate stack is insertedbetween the press roll and the anvil roll and sheared, the thin platestack is sheared without pressing the thin plate stack into the shearingrecess of the anvil roll beyond a thickness of the thin plate stack.Preferably, the thin plate stack is pressed to a position correspondingto a depth in the shearing recess of the anvil roll which is equal to orgreater than a total thickness of the metal layers of the thin platestack and equal to or less than a total thickness of the non-metallayers of the thin plate stack.

As mentioned above, the shearing method of the present invention isapplied to a thin plate prepared by laminating one or more non-metallayers on one or respective ones of opposite surfaces of a metal layer.However, the shearing method of the present invention may also beapplied to a thin plate made of a metal. Specifically, in a shearingmethod using a punch and a die having a shearing hole, a thin plate madeof a metal is placed between the punch and the die, and the punch isrelatively moved toward and with respect to the shearing hole to therebyshear the thin plate, wherein an intermediate plate having at least onenon-metal layer is placed between the thin plate and the punch, and therelative movement of the punch is stopped to complete the shearing ofthe metal plate, before the punch penetrates through the intermediateplate. Preferably, in this case, the relative movement of the punch isstopped at a position corresponding to a depth in a combination of thethin plate and the intermediate plate which is equal to or greater thana thickness of the thin plate and equal to or less than a thickness ofthe intermediate plate.

In a shearing method using a die cutter provided with a convexpush-cutting blade on a surface thereof and an anvil roll provided witha shearing recess at a position corresponding to the convex push-cuttingblade, a thin plate made of a metal is inserted between the die cutterand the anvil roll, and the convex push-cutting blade of the die cutteris rotated and pressed toward the shearing recess of the anvil roll tothereby shear the thin plate, wherein an intermediate plate having atleast one non-metal layer is inserted between the thin plate and the diecutter, and the thin plate is sheared without causing the convexpush-cutting blade of the die cutter to penetrate through theintermediate plate and become fitted into the shearing recess of theanvil roll. Preferably, in this case, the convex push-cutting blade ofthe die cutter is thrust to a position corresponding to a depth in acombination of the thin plate and the intermediate plate which is equalto or greater than a thickness of the thin plate and equal to or lessthan a thickness of the intermediate plate.

In a shearing method using a press roll and an anvil roll provided witha shearing recess, a thin plate made of a metal is inserted between thepress roll and the anvil roll, and the press roll is rotated to pressthe thin plate toward the shearing recess of the anvil roll to therebyshear the thin plate, wherein an intermediate plate having at least onenon-metal layer is inserted between the thin plate and the die cutter,and the thin plate is sheared without pressing the thin plate into theshearing recess of the anvil roll beyond a thickness of the thin plate.In a shearing method using a press roll having a surface coated with alayer including at least one non-metal layer, and an anvil roll providedwith a shearing recess, a thin plate made of metal is inserted betweenthe press roll and the anvil roll, and the press roll is rotated topress the thin plate toward the shearing recess of the anvil roll tothereby shear the thin plate, wherein the thin plate is sheared withoutpressing the thin plate into the shearing recess of the anvil rollbeyond a thickness of the thin plate.

Among the above shearing methods of the present invention, in theshearing method using the die cutter or press roll, the anvil roll andthe intermediate plate, in order to allow the intermediate plate to berepeatedly used, the intermediate plate may be formed in an endlessconfiguration, wherein the intermediate plate is inserted between thedie cutter or press roll and the thin plate or thin plate stack and thenpassed and pressed between a pair of rolls, whereafter the intermediateplate is re-inserted between the die cutter or press roll and the thinplate or thin plate stack.

In the present invention, the anvil roll may be formed such that theshearing recess thereof has a peripheral edge region made of a materialhaving hardness greater than that of the remaining region of the anvilroll. This makes it possible to reliably perform the shearing whilepreventing chipping or the like from occurring in the peripheral edgeregion of the shearing recess which is a shearing area.

Further, the anvil roll may have at least two cutouts provided atrespective positions before and after the shearing recess in a rotationdirection thereof, with a given distance from the shearing recess. Thismakes it possible to prevent the thin plate or thin plate stack frombeing excessively pressed at respective positions before and after theshearing recess and damaged.

Effect of the Invention

In a method of shearing a thin plate which is made of a metal orprepared by laminating one or more non-metal layers on one or respectiveones of opposite surfaces of a metal layer, the present invention makesit possible to shear the thin plate with high quality over a long periodof time while allowing a forming tool to be fabricated at relatively lowcost, and therefore perform the shearing of the thin plate with highquality at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1( a) and 1(b) illustrate basic steps of a shearing methodaccording to a first embodiment of the present invention.

FIGS. 2( a) and 2(b) illustrate a shearing method according to a secondembodiment of the present invention.

FIGS. 3( a) and 3(b) illustrate a shearing method according to a thirdembodiment of the present invention.

FIG. 4 illustrates a shearing method according to a fourth embodiment ofthe present invention.

FIG. 5 illustrates one modification of the embodiment in FIG. 4.

FIG. 6 illustrates a shearing method according to a fifth embodiment ofthe present invention.

FIGS. 7( a) to 7(f) illustrate various examples of a shape of a convexpush-cutting blade of a die cutter, wherein FIG. 7( b), FIG. 7( d) andFIG. 7( f) are sectional views taken along the line A-A in FIG. 7( a),the line B-B in FIG. 7( c) and the line C-C in FIG. 7( e), respectively.

FIG. 8 illustrates a shearing method according to a sixth embodiment ofthe present invention.

FIG. 9 illustrates one modification of the embodiment in FIG. 8.

FIG. 10 illustrates a shearing method according to a seventh embodimentof the present invention.

FIG. 11 illustrates a shearing method according to an eighth embodimentof the present invention.

FIG. 12 illustrates a shearing method according to a ninth embodiment ofthe present invention.

DESCRIPTION OF EMBODIMENTS

With reference to the drawings, the present invention will now bedescribed based on various embodiments thereof.

First Embodiment

FIGS. 1( a) and 1(b) are explanatory diagrams showing basis steps of ashearing method according to a first embodiment of the presentinvention.

In the first embodiment illustrated in FIG. 1, a workpiece plate 1 is anelectrode plate for a lithium-ion battery, which is prepared bylaminating two active material layers (non-metal layers) 1 b onrespective ones of opposite surfaces of a metal layer 1 a made of copperor aluminum. The metal layer 1 a has a thickness of 20 μm, and each ofthe non-metal layers 1 b has a thickness of 80 μm. Thus, a thickness ofthe workpiece plate 1 is 180 μm in total.

As shown in FIG. 1( a), the workpiece plate 1 is placed on and fixed toa die 2 having a shearing hole 2 a. Then, as shown in FIG. 1( b), apunch 3 disposed just above the shearing hole 2 a is moved downwardly toshear the workpiece plate 1.

In the first embodiment, the punch 3 is stopped at a position away froman initial contact position between the punch 3 and an upper surface ofthe workpiece plate 1 by 30 μm, i.e. at a timing when the punch 3 ismoved downwardly (in a depthwise direction of the workpiece plate 1) toa position corresponding to a depth equal to 17% of the thickness of theworkpiece plate 1. In a test carried out under the above conditions, itwas verified that the workpiece plate 1 is fully sheared. A shearedproduct portion of the workpiece plate 1 can be easily extracted bypushing or sucking it from thereabove or therebelow. In the firstembodiment, a clearance between the punch and the die is set to 10 μm.The clearance of 10 μm is a value free of particular difficulty infabricating a forming tool.

As above, in the first embodiment, the workpiece plate 1 is shearedwithout bringing the punch 3 into direct contact with the metal layer 1a located in a central region of the workpiece plate 1, so that itbecomes possible to prevent a metal component of the metal layer 1 afrom adhering to the punch 3 and exerting adverse effects on theshearing. In addition, a problem of roughening of a sheared surfacenever occurs.

Although the first embodiment illustrated in FIG. 1 shows one examplewhere the workpiece plate 1 is sheared which is prepared by laminatingthe two non-metal layers 1 b on respective ones of the opposite surfacesof the metal layer 1 b, it is also possible to shear a workpiece plateprepared by laminating one non-metal layer on one of opposite surfacesof a metal layer, in the same manner. Preferably, in this case, theworkpiece plate is placed such that the non-metal layer is located on anupper side thereof so as to allow the punch to be brought into contactwith the non-metal layer.

In the first embodiment illustrated in FIG. 1, the punch 3 is disposedjust above the die 2. Alternatively, the punch and the die are disposedupside down, i.e., the punch is disposed just below the die. In thefirst embodiment illustrated in FIG. 1, the punch 3 is adapted to bemoved vertically. Alternatively, the die 2 may be adapted to be movedvertically.

Second Embodiment

FIG. 2 illustrates a shearing method according to a second embodiment ofthe present invention. The second embodiment is one example where aplurality of workpiece plates are stacked on each other to form aworkpiece plate stack, and then sheared.

In the second embodiment, each of eight workpiece plates 1 is anelectrode plate for a lithium-ion battery, which has a thickness of 180μm, as with the first embodiment, and they are stacked on each othervertically. Thus, a total thickness of the stacked workpiece plates 1,i.e., workpiece plate stack, is 1.44 mm.

In the second embodiment, the punch 3 is stopped at a position away froman initial contact position between the punch 3 and an upper surface ofthe workpiece plate stack (eight stacked workpiece plates 1) by 200 μm,i.e. at a timing when the punch 3 is moved downwardly (in a depthwisedirection of the workpiece plate stack) to a position corresponding to adepth equal to 14% of the thickness of the workpiece plate stack. In atest carried out under the above conditions, it was verified that all ofthe eight workpiece plates 1 are fully sheared.

Third Embodiment

FIG. 3 illustrates a shearing method according to a third embodiment ofthe present invention. The third embodiment is one example where a thinplate made of a metal is sheared using a punch and a die.

As shown in FIG. 3( a), a thin plate made of a metal, as a workpieceplate 7, is placed on a die 2, and then an intermediate plate 8 havingat least one non-metal layer is placed on the workpiece plate 7. In thethird embodiment, the workpiece plate 7 is comprised of a titanium platehaving a thickness of 20 μm, and the intermediate plate 8 is comprisedof a polypropylene plate having a thickness of 150 μm. As a material ofthe intermediate plate 8, a non-metal layer may be used which is made ofone selected from the group consisting of acrylic resin, PET,polycarbonate, bakelite, plastic, fluororesin, epoxy resin,polyurethane, polyvinyl chloride, polyamide, polyethylene, vinylchloride, hard rubber, paper, glass plate, asphalt and synthetic fiber,as well as polypropylene. Further, a laminated material comprised of twoor more of the non-metal layers or a laminated material comprised of thenon-metal layer and a metal layer may be used.

Then, as shown in FIG. 3( b), a punch 3 disposed just above a shearinghole 2 a of the die is moved downwardly to shear the workpiece plate 7.

In the third embodiment, the punch 3 is stopped at a position away froman initial contact position between the punch 3 and an upper surface ofthe intermediate plate 8 by 40 μm, i.e. at a timing when the punch 3 ismoved downwardly (in a depthwise direction of the intermediate plate 8and the workpiece plate 7) to a position corresponding to a depth whichis equal to or greater than the thickness of the workpiece plate 7 (thethin plate made of a metal) and equal to or less than the thickness ofthe intermediate plate 8, and until before the punch 3 penetratesthrough the intermediate plate 8. In a test carried out under the aboveconditions, it was verified that the workpiece plate 7 is fully sheared.A sheared product portion of the workpiece plate can be easily extractedby pushing or sucking it from thereabove or therebelow.

In the method designed to shear a thin plate made of a metal, throughthe intermediate plate 8, as in the third embodiment, it is preferableto stop the punch 3 before the punch 3 is moved by a distance equal tothe thickness of the thin plate, as the earliest timing, or before thepunch 3 penetrates the intermediate plate 8, as the latest timing, afterthe punch 3 is initially brought into contact with the upper surface ofthe intermediate plate 8. In other words, it is preferable that a thrustdepth after the punch 3 is initially brought into contact with the uppersurface of the intermediate plate 8, is set to a value equal to orgreater than the thickness of the workpiece plate (thin plate made of ametal) and equal to or less than the thickness of the intermediate plate8. A prerequisite in this case is that the thickness of the intermediateplate is greater that the thickness of the workpiece plate (thin platemade of a metal).

Fourth Embodiment

FIG. 4 illustrates a shearing method according to a fourth embodiment ofthe present invention. The fourth embodiment is one example where thepresent invention is applied to a shearing method using a die cut rollconsisting of a die cutter and an anvil roll. A workpiece plate 1 in thefourth embodiment is the same as that in the first embodiment.

As shown in FIG. 4, a die cutter 4 has a convex push-cutting blade 4 aprovided on a surface thereof at a position corresponding to a shearingrecess 5 a of an anvil roll 5. The workpiece plate 1 is inserted betweenthe die cutter 4 and the anvil roll 5 which are rotating in respectiveones of the arrowed directions, and the convex push-cutting blade 4 a ofthe die cutter is rotated and pressed toward the shearing recess 5 a ofthe anvil roll 5 to shear the workpiece plate 1.

In the fourth embodiment, during the shearing operation, the workpieceplate 1 is sheared without causing the convex push-cutting blade 4 a ofthe die cutter to penetrate through the workpiece plate 1 and becomefitted into the shearing recess 5 a of the anvil roll, as shown in FIG.4. In the fourth embodiment, the convex push-cutting blade 4 a is thrustto a position where a distal end thereof is located away from an uppersurface of the workpiece plate 1 by 20 μm, i.e., a positioncorresponding to a depth equal to 11% of the thickness of the workpieceplate 1. In a test carried out under the above conditions, it wasverified that the workpiece plate 1 is fully sheared in the same manneras that in the first embodiment. A sheared product portion of theworkpiece plate can be easily extracted by pushing or sucking it fromthereabove or therebelow.

Although not illustrated, another test was carried out under thefollowing conditions: A workpiece plate stack formed by stacking twoworkpiece plates 1 on each other is inserted between the die cutter 4and the anvil roll 5, and the convex push-cutting blade 4 a is thrust toa position corresponding to a depth equal to 36% of a thickness of theworkpiece plate stack (two stacked workpiece plates 1). As a result, itwas verified that all of the eight workpiece plates 1 are fully shearedin the same manner as that in the second embodiment.

Although the fourth embodiment illustrated in FIG. 4 shows one examplewhere the workpiece plate 1 is sheared which is prepared by laminatingthe two non-metal layers 1 b on respective ones of the opposite surfacesof the metal layer 1 b, it is also possible to shear a workpiece plateprepared by laminating one non-metal layer on one of opposite surfacesof a metal layer, in the same manner. Preferably, in this case, theworkpiece plate is inserted to allow the non-metal layer to come intocontact with the die cutter 4.

FIG. 5 illustrates one modification of the fourth embodiment in FIG. 4.In the modified embodiment illustrated in FIG. 5, an intermediate plate6 having at least one non-metal layer is inserted between the die cutter4 and the workpiece plate 1. Based on interposing the intermediate plate6 in this manner, the workpiece plate 1 can be more reliably sheared bya pressing effect arising from plastic flow of the intermediate plate 6.

Specifically, as the intermediate plate 8, a non-metal layer may be usedwhich is made of one selected from the group consisting of acrylicresin, PET, polycarbonate, bakelite, plastic, fluororesin, epoxy resin,polyurethane, polyvinyl chloride, polyamide, polyethylene,polypropylene, vinyl chloride, hard rubber, paper, glass plate, asphaltand synthetic fiber. Further, a laminated material comprised of two ormore of the non-metal layers or a laminated material comprised of thenon-metal layer and a metal layer may be used.

Fifth Embodiment

FIG. 6 illustrates a shearing method according to a fifth embodiment ofthe present invention. The fifth embodiment is one example where a thinplate made of a metal is sheared using a die cutter and an anvil roll.

As shown in FIG. 6, a die cutter 4 has a convex push-cutting blade 4 aprovided on a surface thereof at a position corresponding to a shearingrecess 5 a of an anvil roll 5. In the fifth embodiment, a thin platemade of a metal, as a workpiece plate 7, is inserted between the diecutter 4 and the anvil roll 5 which are rotating in respective ones ofthe arrowed directions, and an intermediate plate 6 having at least onenon-metal layer is inserted between the die cutter 4 and the workpieceplate 7. Then, the convex push-cutting blade 4 a of the die cutter isrotated so as to press the workpiece plate 7 toward the shearing recess5 a of the anvil roll 5 through the intermediate plate 6 to shear theworkpiece plate 7. During the shearing operation, the workpiece plate 7is sheared without causing the convex push-cutting blade 4 a of the diecutter to penetrate through the intermediate plate 6 and the workpieceplate 7 and become fitted into the shearing recess 5 a of the anvilroll.

In the method designed to shear the workpiece plate 7 (thin plate madeof a metal) by the die cut roll through the intermediate plate 8, as inthe fifth embodiment, it is preferable to set a distance (gap) betweenthe die cutter 4 and the anvil roll 5, based on the same criteria asthat in the third embodiment, in such a manner that a thrust depth ofthe workpiece plate (thin plate made of a metal) and the intermediateplate into the shearing recess 5 a of the anvil roll becomes equal to orgreater than a thickness of the workpiece plate and equal to or lessthan a thickness of the intermediate plate. In other words, it ispreferable that the distance (gap) between the die cutter 4 and theanvil roll 5 is set to a value equal to or less than [(the thickness ofthe workpiece plate+the thickness of the intermediate plate)−thethickness of the workpiece plate] and equal to or greater than thethickness of the workpiece plate. A prerequisite in this case is thatthe thickness of the intermediate plate is greater that the thickness ofthe workpiece plate (thin plate made of a metal).

According to experimental tests carried out by the inventor, in thefourth and fifth embodiments using the die cutter 4 and the anvil roll5, it is preferable that an outer peripheral shape of the convexpush-cutting blade 4 a of the die cutter is set to be equal to orslightly greater than an inner peripheral shape of the shearing recess 5a of the anvil roll. Specifically, as shown in FIG. 4, it is preferableto satisfy the following relationship: B≦A≦1.1 B, where A is a length ofone of four sides of the outer peripheral shape of the convexpush-cutting blade 4 a, and B is a length of a corresponding one of foursides of the inner peripheral shape of the shearing recess 5 a. Thereason is that, if A is less than B, burrs are likely to occur in asheared portion, which causes deterioration in quality of a shearedsurface. On the other hand, if A is greater than 1.1 B, a pressingportion, i.e., an area pressing the workpiece plate, becomes excessivelywidened, which causes deterioration in quality of the workpiece plate.

A shape of the convex push-cutting blade 4 a of the die cutter for usein the present invention will be described below. In shearing using thedie cutter, as shown in FIGS. 7( a) and 7(b), the convex push-cuttingblade 4 a of the die cutter is typically formed such that only an outerperipheral portion thereof protrudes outwardly to have an acute distalend. In the present invention, the convex push-cutting blade 4 a is notnecessarily formed in a protruding shape with an acute distal end asshown in FIGS. 7( a) and 7(b), because it is based on shearing. Thus,the convex push-cutting blade 4 a may be formed to protrude in itsentirety to have a right-angled edge as shown in FIGS. 7( c) and 7(d),or may be formed to protrude in its entirety to have an obtuse-anglededge s shown in FIGS. 7( e) and 7(f). Further, the edge may be roundedas indicated by the broken lines in FIGS. 7( d) and 7(f).

Sixth Embodiment

FIG. 8 illustrates a shearing method according to a sixth embodiment ofthe present invention. The sixth embodiment is one example where aworkpiece plate is sheared using a press roll and an anvil roll. Aworkpiece plate 1 in the sixth embodiment is the same as that in thefirst embodiment.

As shown in FIG. 8, a press roll 9 has a smooth surface devoid of theconvex push-cutting blade. An anvil roll 5 disposed opposed to the pressroll 9 has a shearing recess 5 a provided in a surface thereof inconformity to a shape of a product to be cut off. In the sixthembodiment, the workpiece plate 1 is inserted between the press roll 9and the anvil roll 5 which are rotating in respective ones of thearrowed directions, and an intermediate plate 6 having at least onenon-metal layer is inserted between the press roll 9 and the workpieceplate 1.

Then, the press roll 9 is rotated so as to press the workpiece plate 1toward the shearing recess 5 a of the anvil roll to shear the workpieceplate 1. During the shearing operation, the workpiece plate 1 is shearedwithout pressing the workpiece plate 1 into the shearing recess 5 a ofthe anvil roll beyond a thickness of the workpiece plate 1.Specifically, the workpiece plate 1 is pressed to a positioncorresponding to a depth in the shearing recess 5 a of the anvil rollwhich is equal to or greater than a thickness of a metal layer 1 a andequal to or less than a total thickness of one or more non-metal layers1 b of the workpiece plate 1. In a test, the workpiece plate 1 wasactually pressed into the shearing recess 5 a of the anvil roll by adepth of 20 μm. As a result, it was verified that the workpiece plate 1is fully sheared.

Although not illustrated, another test was carried out under thefollowing conditions: A workpiece plate stack formed by stacking twoworkpiece plates 1 on each other is inserted between the press roll 9and the anvil roll 5, and pressed into the shearing recess 5 a of theanvil roll by a depth of 80 μm. As a result, it was verified that bothof the two workpiece plates 1 are fully sheared.

FIG. 9 illustrates one modification of the sixth embodiment in FIG. 8.In the modified embodiment illustrated in FIG. 9, a thin plate made of ametal is sheared as a workpiece plate 7. Specifically, the press roll 9is rotated so as to press the workpiece plate 7 into the shearing recess5 a of the anvil roll through an intermediate plate 6 to shear theworkpiece plate 7.

More specifically, the workpiece plate is comprised of an aluminum foilhaving a thickness of 20 μm, and the intermediate plate 6 is comprisedof a PET resin having a thickness of 500 μm. Further, a distance (gap)between the press roll 9 and the anvil roll 5 is set to 500 μm. In atest carried out under the above conditions, it was verified that theworkpiece plate 7 is fully sheared.

Seventh Embodiment

FIG. 10 illustrates a shearing method according to a seventh embodimentof the present invention. In the embodiments illustrated in FIGS. 5, 6,8 and 9, the intermediate plate 6 to be inserted between the workpieceplate 1(7) and the die cutter 4 or press roll 9 is formed as adisposable type. Differently, an intermediate plate 6 in the seventhembodiment is formed as a repeatedly usable type.

Specifically, as shown in FIG. 10, the intermediate plate 6 is formed inan endless configuration. The intermediate plate 6 is inserted between adie cutter 4 and a workpiece plate 1 (7) so as to be used for shearingto and then passed between a pair of rolls 10, 10, whereafter theintermediate plate 6 is re-inserted between the die cutter 4 and theworkpiece plate 1 (7). Thus, even if plastic deformation correspondingto a shearing recess 5 a of the anvil roll (a convex push-cutting blade4 a of the die cutter) occurs in the intermediate plate 6 used for theshearing, due to the pressing during the shearing, the intermediateplate 6 is subsequently passed and pressed between the rolls 10, 10 andreturned to a shape approximately identical to its original shape, sothat it can be repeatedly used, which is also advantageous in terms ofcost.

In cases where the intermediate plate is repeatedly used, it ispreferable that a flexible material such a rubber is used as a materialfor the intermediate plate 6 to allow the intermediate plate 6 to beeasily returned to the original shape. Although the seventh embodimentin FIG. 10 shows one example using the die cutter 4, it is understoodthat a press roll may be used instead of the die cutter 4.

Eighth Embodiment

FIG. 11 illustrates a shearing method according to an eighth embodimentof the present invention. The eighth embodiment is one example where asurface of a press roll 9 is coated with an outer layer 9 a including atleast one non-metal layer, instead of inserting an intermediate layerbetween the press roll 9 and a workpiece plate 1(7).

The shearing method according to the eighth embodiment is capable ofperforming shearing in the same manner as that in the shearing methoddesigned to insert the intermediate plate between the press roll 9 andthe workpiece plate 1(7), and avoiding using the intermediate plate in athrowaway manner. During shearing, the workpiece plate 1(7) is shearedwithout pressing the workpiece plate 1(7) into a shearing recess 5 a ofan anvil roll beyond a thickness of the workpiece plate 1(7).Preferably, the outer layer 9 a is made of a flexible material such arubber to allow the outer layer 9 a to be easily returned to itsoriginal shape.

Ninth Embodiment

FIG. 12 illustrates a shearing method according to a ninth embodiment ofthe present invention. In the ninth embodiment, at least two cutouts 5 bare provided at respective positions before and after a shearing recess5 a of an anvil roll 5 in a rotation direction thereof, with a givendistance from the shearing recess 5 a.

Based on providing the cutout 5 b in this manner, it becomes possible toprevent a workpiece plate 1(7) from being pressed between a die cutter 4and a portion of an anvil roll 5 unnecessary for shearing of a workpieceplate 1(7). In other words, an outer peripheral portion of the anvilroll 5 having a length L between a shearing recess 5 a of the anvil rolland each of the cutouts 5 a is a region required for the shearing of theworkpiece plate 1(7). Thus, the cutouts 5 b are provided while leavingthe regions, so that it becomes possible to prevent the workpiece plate1(7) from being pressed between the die cutter 4 and the portion of theanvil roll 5 unnecessary for the shearing, while allowing for theshearing of the workpiece plate 1(7). This makes it possible to preventthe workpiece plate 1(7) from being damaged due to unnecessary pressing.Particularly, in a workpiece plate having an active material layer(non-metal layer) on a surface thereof as used in the first embodiment,the active material layer is brittle and damageable. Thus, the ninthembodiment is effective in such a workpiece plate.

Depending on a diameter of the anvil roll, it is desirable to set thelength L in the range of 0.5 to 2 mm. If the length L is less than 0.5mm, the anvil roll is likely to damage a surface region of the workpieceplate around a sheared surface. If the length L is greater than 2 mm, apressing portion, i.e., an area pressing the workpiece plate, becomesexcessively widened, which accelerates damage of the workpiece plate.Thus, it is most preferable to set the length L in the range of 0.5 to 2mm, in view of preventing damage of a surface of the workpiece plate andminimizing the pressing portion. Although the ninth embodiment in FIG.12 shows one example using the die cutter 4, it is understood that apress roll may be used instead of the die cutter 4.

In cases where an anvil roll is used in the above embodiments, it ispreferable that a peripheral edge region of a shearing recess of theanvil roll is made of a material having hardness greater than that ofthe remaining region of the anvil roll. For example, the peripheral edgeregion of the shearing recess may be made of hard metal, ceramics or DCLcoating. This makes it possible to prevent chipping or the like in theperipheral edge portion of the shearing recess which is a shearing area.

Further, preferably, each of the die cutter, the press roll and a bodyof the anvil roll is made of a material having a capability tofacilitate ensuring machining accuracy, and a Young's modulus of 150 GPaor more.

EXPLANATION OF CODES

-   1: workpiece plate (thin plate including non-metal layer)-   1 a: metal layer-   1 b: non-metal layer-   2: die-   2 a: shearing hole-   3: punch-   4: die cutter-   4 a: convex push-cutting blade-   5: anvil roll-   5 a: shearing recess-   5 b: cutout-   6: intermediate plate-   7: workpiece plate (thin plate made of metal)-   8: intermediate plate-   9: press roll-   9 a: outer layer-   10: roll

1. A method of shearing a thin plate prepared by laminating one or morenon-metal layers on one or respective ones of opposite surfaces of ametal layer, comprising: placing the thin plate between a punch and adie having a shearing hole; and relatively moving the punch toward andwith respect to the shearing hole to thereby shear the thin plate,wherein the relative movement of the punch is stopped to complete theshearing, before the punch penetrates through the thin plate and becomesfitted into the shearing hole.
 2. The method as defined in claim 1,wherein the metal layer of the thin plate has a thickness less than atotal thickness of the one or more non-metal layers of the thin plate,and wherein the relative movement of the punch is stopped at a positioncorresponding to a depth in the thin plate which is equal to or greaterthan the thickness of the metal layer and equal to or less than thetotal thickness of the one or more non-metal layers.
 3. The method asdefined in claim 1, wherein a plurality of the thin plates are stackedon each other to form a thin plate stack and placed between the punchand the die, and wherein the relative movement of the punch is stoppedto complete the shearing, before the punch penetrates through the thinplate stack and becomes fitted into the shearing hole.
 4. The method asdefined in claim 3, wherein the metal layer of the thin plate has athickness less than a total thickness of the one or more non-metallayers of the thin plate, and wherein the relative movement of the punchis stopped at a position corresponding a depth in the thin plate stackwhich is equal to or greater than a total thickness of the metal layersof the thin plate stack and equal to or less than a total thickness ofthe non-metal layers of the thin plate stack.
 5. A method of shearing athin plate made of a metal, comprising: placing the thin plate between apunch and a die having a shearing hole; and relatively moving the punchtoward and with respect to the shearing hole to thereby shear the thinplate, wherein an intermediate plate having at least one non-metal layeris placed between the thin plate and the punch, and the relativemovement of the punch is stopped to complete the shearing, before thepunch penetrates through the intermediate plate.
 6. The method asdefined in claim 5, wherein the thin plate has a thickness less thanthat of the intermediate plate, and wherein the relative movement of thepunch is stopped at a position corresponding to a depth in a combinationof the thin plate and the intermediate plate which is equal to orgreater than the thickness of the thin plate and equal to or less thanthe thickness of the intermediate plate.
 7. A method of shearing a thinplate prepared by laminating one or more non-metal layers on one orrespective ones of opposite surfaces of a metal layer, comprising:inserting the thin plate between a die cutter provided with a convexpush-cutting blade on a surface thereof, and an anvil roll provided witha shearing recess at a position corresponding to the convex push-cuttingblade; and rotating and pressing the convex push-cutting blade of thedie cutter toward the shearing recess of the anvil roll to thereby shearthe thin plate, wherein the thin plate is sheared without causing theconvex push-cutting blade of the die cutter to penetrate through thethin plate and become fitted into the shearing recess of the anvil roll.8. The method as defined in claim 7, wherein the metal layer of the thinplate has a thickness less than a total thickness of the one or morenon-metal layers of the thin plate, and wherein the convex push-cuttingblade of the die cutter is thrust to a position corresponding to a depthin the thin plate which is equal to or greater than the thickness of themetal layer and equal to or less than the total thickness of the one ormore non-metal layers.
 9. The method as defined in claim 7, wherein aplurality of the thin plates are stacked on each other to form a thinplate stack and inserted between the die cutter and the anvil roll,wherein all of the thin plates are sheared without causing the convexpush-cutting blade of the die cutter to penetrate through the thin platestack and become fitted into the shearing recess of the anvil roll. 10.The method as defined in claim 9, wherein the metal layer of the thinplate has a thickness less than a total thickness of the one or morenon-metal layers of the thin plate, and wherein the convex push-cuttingblade of the die cutter is thrust to a position corresponding to a depthin the thin plate stack which is equal to or greater than a totalthickness of the metal layers of the thin plate stack and equal to orless than a total thickness of the non-metal layers of the thin platestack.
 11. The method as defined in claim 7, wherein an intermediateplate having at least one non-metal layer is inserted between the diecutter and the thin plate or thin plate stack.
 12. The method as definedin claim 11, wherein the metal layer of the thin plate has a thicknessless than a total thickness of the one or more non-metal layers of thethin plate and a thickness of the intermediate plate, and wherein theconvex push-cutting blade of the die cutter is thrust to a positioncorresponding to a depth in a combination of the intermediate plate andthe thin plate or thin plate stack which is equal to or greater than atotal thickness of the metal layers of the thin plate or thin platestack and equal to or less than a total thickness of the non-metallayers of the thin plate or thin plate stack and the intermediate plate.13. The method as defined in claim 11, wherein the intermediate plate isformed in an endless configuration, and wherein the intermediate plateis inserted between the die cutter and the thin plate or thin platestack and then passed and pressed between a pair of rolls, whereafterthe intermediate plate is re-inserted between the die cutter and thethin plate or thin plate stack.
 14. The method as defined in claim 7,wherein the shearing recess of the anvil roll has a peripheral edgeregion made of a material having hardness greater than that of theremaining region of the anvil roll.
 15. The method as defined in claim7, wherein the anvil roll has at least two cutouts provided atrespective positions before and after the shearing recess in a rotationdirection thereof, with a given distance from the shearing recess.
 16. Amethod of shearing a thin plate made of a metal, comprising: insertingthe thin plate between a die cutter provided with a convex push-cuttingblade on a surface thereof, and an anvil roll provided with a shearingrecess at a position corresponding to the convex push-cutting blade; androtating and pressing the convex push-cutting blade of the die cuttertoward the shearing recess of the anvil roll to thereby shear the thinplate, wherein an intermediate plate having at least one non-metal layeris inserted between the thin plate and the die cutter, and the thinplate is sheared without causing the convex push-cutting blade of thedie cutter to penetrate through the intermediate plate and become fittedinto the shearing recess of the anvil roll.
 17. The method as defined inclaim 16, wherein the thin plate has a thickness less than that of theintermediate plate, and wherein the convex push-cutting blade of the diecutter is thrust to a position corresponding to a depth in a combinationof the thin plate and the intermediate plate which is equal to orgreater than the thickness of the thin plate and equal to or less thanthe thickness of the intermediate plate.
 18. The method as defined inclaim 16, wherein the intermediate plate is formed in an endlessconfiguration, and wherein the intermediate plate is inserted betweenthe die cutter and the thin plate and then passed and pressed betweenthe die cutter and the anvil roll, whereafter the intermediate plate isre-inserted between the die cutter and the thin plate.
 19. The method asdefined in claim 16, wherein the shearing recess of the anvil roll has aperipheral edge region made of a material having hardness greater thanthat of the remaining region of the anvil roll.
 20. The method asdefined in claim 16, wherein the anvil roll has at least two cutoutsprovided at respective positions before and after the shearing recess ina rotation direction thereof, with a given distance from the shearingrecess.
 21. A method of shearing a thin plate which is made of a metalor prepared by laminating one or more non-metal layers on one orrespective ones of opposite surfaces of a metal layer, comprising:inserting the thin plate between a press roll, and an anvil rollprovided with a shearing recess; and rotating the press roll to pressthe thin plate toward the shearing recess of the anvil roll to therebyshear the thin plate, wherein an intermediate plate having at least onenon-metal layer is inserted between the thin plate and the press roll,and the thin plate is sheared without pressing the thin plate into theshearing recess of the anvil roll beyond a thickness of the thin plate.22. The method as defined in claim 21, wherein the thin plate isprepared by laminating one or more non-metal layers on one or respectiveones of opposite surfaces of a metal layer, and wherein the thin plateis pressed to a position corresponding to a depth in the shearing recessof the anvil roll which is equal to or greater than a thickness of themetal layer and equal to or less than a total thickness of the one ormore non-metal layers of the thin plate.
 23. The method as defined inclaim 21, wherein the thin plate is prepared by laminating one or morenon-metal layers on one or respective ones of opposite surfaces of ametal layer, and wherein a plurality of the thin plates are stacked oneach other to form a thin plate stack, and wherein the intermediateplate having at least one non-metal layer is inserted between the thinplate stack and the press roll, and the thin plate stack is shearedwithout pressing the thin plate stack into the shearing recess of theanvil roll beyond a thickness of the thin plate stack.
 24. The method asdefined in claim 23, wherein the thin plate stack is pressed to aposition corresponding to a depth in the shearing recess of the anvilroll which is equal to or greater than a total thickness of the metallayers of the thin plate stack and equal to or less than a totalthickness of the non-metal layers of the thin plate stack.
 25. Themethod as defined in claim 21, wherein the intermediate plate is formedin an endless configuration, and wherein the intermediate plate isinserted between the press roll and the thin plate or thin plate stackand then passed and pressed between a pair of rolls, whereafter theintermediate plate is re-inserted between the press roll and the thinplate or thin plate stack.
 26. The method as defined in claim 21,wherein the shearing recess of the anvil roll has a peripheral edgeregion made of a material having hardness greater than that of theremaining region of the anvil roll.
 27. The method as defined in claim21, wherein the anvil roll has at least two cutouts provided atrespective positions before and after the shearing recess in a rotationdirection thereof, with a given distance from the shearing recess.
 28. Amethod of shearing a thin plate which is made of a metal or prepared bylaminating one or more non-metal layers on one or respective ones ofopposite surfaces of a metal layer, comprising: inserting the thin platebetween a press roll having a surface coated with a layer including atleast one non-metal layer, and an anvil roll provided with a shearingrecess; and rotating the press roll to press the thin plate toward theshearing recess of the anvil roll to thereby shear the thin plate,wherein the thin plate is sheared without pressing the thin plate intothe shearing recess of the anvil roll beyond a thickness of the thinplate.
 29. The method as defined in claim 28, wherein the thin plate isprepared by laminating one or more non-metal layers on one or respectiveones of opposite surfaces of a metal layer, and wherein the thin plateis pressed to a position corresponding to a depth in the shearing recessof the anvil roll which is equal to or greater than a thickness of themetal layer and equal to or less than a total thickness of the one ormore non-metal layers of the thin plate.
 30. The method as defined inclaim 28, wherein the thin plate is prepared by laminating one or morenon-metal layers on one or respective ones of opposite surfaces of ametal layer, and wherein a plurality of the thin plates are stacked oneach other to form a thin plate stack, and wherein the thin plate stackis inserted between the press roll and the anvil roll, and shearedwithout pressing the thin plate stack into the shearing recess of theanvil roll beyond a thickness of the thin plate stack.
 31. The method asdefined in claim 30, wherein the thin plate stack is pressed to aposition corresponding to a depth in the shearing recess of the anvilroll which is equal to or greater than a total thickness of the metallayers of the thin plate stack and equal to or less than a totalthickness of the non-metal layers of the thin plate stack.
 32. Themethod as defined in claim 28, wherein the shearing recess of the anvilroll has a peripheral edge region made of a material having hardnessgreater than that of the remaining region of the anvil roll.
 33. Themethod as defined in claim 28, wherein the anvil roll has at least twocutouts provided at respective positions before and after the shearingrecess in a rotation direction thereof, with a given distance from theshearing recess.